Ag Biotechnology: The Bad and the Beautiful?

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14 Δεκ 2012 (πριν από 4 χρόνια και 4 μήνες)

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Ag Biotech Risks in Context


John W. Radin


USDA
-
ARS

Definition of Biotechnology

“The application of science and engineering in the direct
and indirect use of living organisms, or parts or
products of living organisms, in their natural or
modified forms”
---

[Agric. and Agri
-
Food Canada]



“…a collection of scientific techniques…that are
used to create, improve, or modify plants, animals,
and microorganisms”
---

[U.S. Dept. Agriculture]


Many Types of Biotechnology


Molecular markers for breeding


DNA sequencing and genomics


Monoclonal antibodies


Somatic cell and nuclear fusion


Genetic engineering


Biological processing



Traditional” Biotechnology



Making bread



Fermenting wine



Producing cheese




Biotechnology that Transfers Genes
is the Focus of Attention


Molecular markers for breeding


DNA sequencing and genomics


Monoclonal antibodies


Somatic cell and nuclear fusion


Genetic engineering


Biological processing


Why is Genetic Engineering “Bad?”

This technology can move genes and the
traits they dictate
across natural
boundaries

--

from one type of plant to
another, from one type of animal to another,
and even from a plant to an animal or an
animal to a plant.



---

Union of Concerned
Scientists

Crop Breeding Involves “Unnatural”
DNA Recombination and Alteration


Induced mutations: radiation,
chemicals


Wide crosses (outside the “natural”
species barrier)


Chromosome doubling


Embryo rescue


Chromosome substitution lines


Some Crops With Foreign Genes


Wheat


Cotton


Rice


Tomato


Peanut


Sugarcane


Citrus

“Natural Reproductive Boundaries”
are Not Natural Boundaries


DNA sequences of viral origin in plants


DNA sequences of bacterial origin in
plants


Allopolyploidy in plants


DNA transfer between vegetative
fungal strains

Some Risks from Introducing Foreign
Genes (by Any Process)

1.
New food safety hazards, such as
allergens

2.
Unknown ecological impacts of new
plant
-
incorporated protectants (PIP’s)
for pest resistance

3.
Gene flow to related species

4.
Outcrossing to neighboring crop fields


Risk Abatement Strategies: Allergens


Use gene sources with no history of
allergenicity


Test homology between new gene
product and known allergens*


Test digestibility of new gene product*


Test on humans


Provide regulatory oversight (FDA)

*Not applicable to conventional crops

Risk Abatement Strategies: New
PIP’s


Choose genes specific for target pests*


Limit gene expression to tissues and
developmental stages under attack*


Test and monitor ecological effects


Provide regulatory oversight (EPA)*

*Not applicable to conventional crops

Risk Abatement Strategies: Gene
Flow to Native Plants


Put new genes under maternal inheritance*


Couple new genes to a sterility mechanism*


Test and monitor gene movement


Provide regulatory oversight (USDA)*

*Not applicable to conventional
crops

Risk Abatement: Outcrossing to
Neighboring Fields


Put new genes under maternal
inheritance*


Couple new genes to sterility mechanism*


Buffer zones


Test and monitor gene movement

*Not applicable to conventional crops

Conclusions

1.
Mother Nature was the original genetic
engineer.

2.
Conventional plant breeders were the
second genetic engineers.

3.
Genetic improvement of crops always
creates risks of new allergens, new
toxicants, and gene flow to nearby
plants.

Conclusions (cont’d)

4.
Genetic engineering allows risk
reduction by numerous pathways not
available to conventional breeding.

5.
Genetic engineering does increase the
genetic choices available for crop
improvement.
Regulatory systems
must evolve along with the technology,
to maintain sensible rules about
exercising the choices wisely.


Ag Biotech Risks in Context

Degree of regulation
should match the
degree of risk

Risk from conventional
crops is small enough to be
mostly unregulated

Genetic engineering will
probably increase some
crop risks, but decrease
others

Sensible regulation,
based on risk
comparisons to
conventional crops, will
support safety
AND

progress

Agriculture: Caught in a Painful Transition




Ella Fitzgerald on Ag
Biotech:

The Best
is Yet to
Come